API clean up (part 2), plus misc changes and improvements.

- Rename regpkgs_dictionary to regpkgdb_dictionary to better describe what is is.
- Change some funcs in plist.c to return a boolean rather than int.
- Hide more internal funcs off the API.
- Simplify xbps_repository_update_pkg() and remove its second arg.
- Hide implementation details in xbps_repository_pool, now to iterate over the
  pool you have to use xbps_repository_pool_foreach and its struct
  repository_pool_index.
- Introduce xbps_{init,end}, to initialize/destroy some stuff in the library.
- Introduce xbps_dbg_printf to printf stuff for debugging purposes.
- xbps-{bin,repo}:  added -d arg to enable debugging output.
- Before checking if a config file needs to be installed or such, check that
  package contains the "conf_files" array.
- Remove obsolete dirs as well while updating packages.
- If transaction dictionary is ready remove the "missing_deps" array.

Bump XBPS_RELVER to 20101118.

--HG--
rename : lib/regpkgs_dictionary.c => lib/regpkgdb_dictionary.c

bin/xbps-bin/check.c

@@ -29,6 +29,7 @@
 #include <string.h>
 #include <errno.h>
 #include <assert.h>
+#include <unistd.h>
 
 #include <xbps_api.h>
 #include "defs.h"
@@ -56,7 +57,7 @@ xbps_check_pkg_integrity_all(void)
 	int rv = 0;
 	size_t npkgs = 0, nbrokenpkgs = 0;
 
-	d = xbps_regpkgs_dictionary_init();
+	d = xbps_regpkgdb_dictionary_get();
 	if (d == NULL)
 		return ENODEV;
 
@@ -82,7 +83,7 @@ out:
 	if (iter)
 		prop_object_iterator_release(iter);
 
-	xbps_regpkgs_dictionary_release();
+	xbps_regpkgdb_dictionary_release();
 
 	return rv;
 }